In many applications tubeform-type isolators are used to carry load, accommodate motion, and isolate vibrations between relatively moving structures. One demanding application for such isolators is for isolation of the thrust reverser doors 12 on an aircraft engine 10, as shown in FIGS. 1a and 1f. Heretofore, elastomeric tubeform isolators 11, such as the one shown in partial cross section in FIG. 1e have been utilized. A pylon structure 9 shown in FIGS. 1a and 1b supports the weight of the engine 10 and interconnects the engine 10 to the wing or other structure (not shown). Attached to pylon 9 are various brackets 15, 15' (See enlarged FIGS. 1c and 1d) which have the tubeform isolators 11 secured within their ends. The isolators 11 function to prevent a hard structural transmission path which would enable vibration from the engine to be transmitted from the thrust reverser door 12 into the pylon 9. Further, isolators 11 accommodate axial and radial motions resulting from static and transient engine movements relative to the pylon. It should be understood that the engine 10 is suspended relative to the pylon structure 9 by flexible engine mounts (not shown). Therefore, some radial and/or axial movement of the engine 10 will occur due to transient loads.
The prior art elastomeric thrust reverser isolator 11 is best seen in FIG. 1e and includes a cylindrical inner member 14 having a throughbore through which a thrust reverser door pin 22 is closely received, and a tubular outer member 16 which is received in a bore formed in pylon bracket 15, 15'. Annular elastomer 18 is bonded to both the outer member 16 and inner member 14 and provides flexibility for motion accommodation and isolation. Preferably, a V-groove 19 or the like is staked over to secure isolator 11 in the bore formed in pylon bracket 15, 15'.
Although, the tubeform isolators 11 are adequate for some applications, the thrust reverser door application is very demanding because of high load and motion conditions encountered. For example, during maintenance of the engine 10, the thrust reverser door(s) 12 may be opened by pivoting about the thrust reverser hinge pin(s) 22 as shown in FIG. 1f. Hydraulic jacks 17 provide the lift force needed between the engine casing 13 and the thrust reverser door 12 to allow pivoting about hinge pins 22. During maintenance, significant static radial, torsional, and cocking loads are applied to the isolators 11 due to static loads and torsional and cocking moments resulting from the door weight and pivoting. Over time, this, as well as normal wear and tear on the isolators, severely stresses the elastomer and bond leading to a condition where replacement of the elastomeric isolator 11 is warranted. Further, once staked into the pylon bracket 15, 15', removal/changeout of the isolator 11 is a difficult and time consuming operation. Therefore, there is a long felt and unmet need for an isolator, such as for the thrust reverser isolator application, with improved ability to be quickly changed out, and/or which exhibits improved life as compared to the prior art tubeform isolators.